I first started having problems when I tried to add a memory stick to my pc and when i started my computer the screen did not turn on. If i turn it off and on it would sometimes start. I had the drive diskette drive 0 seek failure and after googling that I replaced the battery on my motherboard and then took out starting a floppy (which i dont have) under the set up as directed which stopped the error message.
But my computer still only occasionsly turns on even after I took the extra memory out. It will always sound like its turning on but usually the monitor doesnt sense it and when my computer does happen to boot, I can only go in through safe mode. And when I do get in through safe mode it is only a matter of minutes before my computer freezes and ctrl+alt+dlt does nothing and I have to turn my computer off.
I have windows xp and a dell dimension 8300.
I am hoping I just have to change something in the setup (f2) when it first turns on as some of the settings reset when I changed the battery in the motherboard, otherwise I have no clue why my computer is acting up. I have system restored, checked for viruses, loose cables, etc.

I would start by re-seating your RAM as well as the graphics card and check all internal connections.

Try to start with the case open and verify that all the fans are running.

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